Helical Diff

[Bl4cK32]

Sick of my clunking 2 way as its a mainly street driven car....

3 options :

1) S15 centre - whats the go with installing this into my r32? What do i do about the half shaft bolt pattern, as i understand u need to use the s15 half shafts. Are the s15 and r32 halfshafts interchangeable?

2)Quaife (torsen) centre - very expensive, but it is a straight drop in i believe?

3)R34 GTR V-spec - i think i read somewhere that they came out with a helical centre....but whats the chance of picking one these up...

This link gives info on how they work, and how the more popular clutch centre works, as well as the pros and cons of each. - http://www.houseofthud.com/differentials.htm

Im just after a centre that doesnt clunck at low speeds, as well as the performance of a locking diff....

So - Looking at the above options 1) seems the cheapest. What is required for the s15 centre to go into my car?

Any other opinions or options are welcome

edit/ as a side note, im also lowering the ratio from 4.3 to 3.9

Edited November 20, 2005 by Bl4cK32

[Nathan_G1]

wat 2-way are u running in ur car currently.......if its done low k's would u consider selling it?

im after one for drift badly

[Bl4cK32]

Nismo GT-Pro 2 way with adjustable pre load.

I would sell it if the price was right. Remember this is the GT-pro though, cos the regular one which isnt adjustable goes for like 1k

Its done less than 10,000. Previous owner ran it in, then ive used it for less than 5,000kms...had 2 or 3 oil changes since new too...came with new everything-sideshaft bearings etc....

attached pic shows what i mean...mines set to soft atm.

On topic - Anyone can help me?

[Duncan]

well if I was looking for a diff I would offer to take it off your hands for free

All you need to do is adjust the preload, that is the only thing that makes it so tight the wheels skip. If they still skip at minimum load you need to get the centre out and remove a shim or two from each side, its that easy.

There is nothing about a mechanical diff that makes it tight except the shims

On the other hand, once you are happy with how tight it is, they are unbeatable for driving performance.

[MerlinTheHapyPig]

yeah, i've heard nismo gt-pro's are quite tight.

eventually the shims will wear out a bit and it'll loosen up, man i would kill for a nice tight 2-way like that( toite like a tiger...). but i'm too poor

/pulls out the mig welder

Edited November 20, 2005 by MerlinTheHapyPig

[Nathan_G1]

il take it off ya hands 4 sure bro.......how much do u actually want, i got a quote from Japanparts.co.jp for the same diff delivered to my door for 1380.....brand spanker.....il give u 1100 no bullsh*t

[Bl4cK32]

All you need to do is adjust the preload, that is the only thing that makes it so tight the wheels skip.  If they still skip at minimum load you need to get the centre out and remove a shim or two from each side, its that easy.

There is nothing about a mechanical diff that makes it tight except the shims

<{POST_SNAPBACK}>

Define what you mean by skip please Duncan?

I think i know what your geting at. I'll adjust up the setting and see how it goes and report back

[Duncan]

sorry, i assumed the thing that was pissing you off about it is that when you do tight turns at slow speeds the inside wheel skips making a nasty clunking / shuddering?

I can't think of any other problem you would notice with a tight diff?

Just loosen it off enough so it doesn't annoy you

[Bl4cK32]

Trying to get my head around it still sorry Duncan

By loosening it off do you mean tightening or softening the pre-load? Its set to the softest (low) setting atm.

Does that mean the only option is to remove a shim or two?

And by doing this, it will effectivly stop the clunking / shuddering etc at slow speeds?

Sorry for the Q's One last one though - I still like the idea of the helical diff because of the non service aspect (clutches to wear out). Which one would you put in a street car, and why?

Edited November 20, 2005 by Bl4cK32

[Nathan_G1]

Il give you my diff if you sell me yours and u can just shim that? that'l stop your clunking, i just need a 2-way and getting it for that price is killa

[Bl4cK32]

I sent an email to Quaife and and still waiting to hear back.

OR - i need to find out how to fit a s15 helical centre to my car, as the half shafts (going from viscous to helical) are different (length and bolt pattern)

im not after a shimmed std diff I want to go helical as there is no maintenance. Shimmed std. will last sfa. I need a replacement helical, or i keep the one i got

[MerlinTheHapyPig]

sounds expensive though. let me know what they say.

But, for the $2k+ this thing may cost you. Is it worth it? your nismo gt will last ages if it's only done 5000kms and is still nice and tight

so, expect to get $1k for your old diff, $1k difference will pay for at least one diff recondition down the track.

If you don't drift, it should last 1-2 years easily i reckon, I know people who have had 2-ways last them longer than 1 year with regular drift without reshim (diff in question is still working great)...

no maintenence? any lsd will require regular oil replacement etc.

Edited November 21, 2005 by MerlinTheHapyPig

[Bl4cK32]

Im really after info on how to do the s15 swap. This is my first choice, beacause as you say the Quaife is an expensive option. S15 centres are helical, and they drop in, its just the damn half shafts...

I know the oil changes count as maintenance, i was referring to pulling the whole diff out for new clutch plates etc...

[T04GTR]

factory helical difs are fantastic with standard power.

put some torque through them and bang.

the lsd efct is done through the gears trying to push themselvs apart in the centre against the centret casing(in short).

the gears simply arnt strong enough for the extra power.

if they open wheel(which they do)it doent take long for them to break

a good mechanical clutch pack lsd is the go.

ps the halfshafts are all diferant on the inside of the diff.

also r34gtt manuel cars come with a helical centre. gtr does not.

cheerrs.

[Bl4cK32]

They must be strong or Quaife wouldnt offer a lifetime warranty with them. This warranty applies even when raced - no one else does this. Quote "proven in everything from SCCA Rally to Formula 1"

Nissan must have thought they were better as they swapped using the vlsd for the hlsd from the s15, and the r34's...

I agree with what most of you guys have said about clutch pack lsd's. Im just getting sick of the shudder. My car isnt too bad with the wheel chirping. I can live with chirps, but shudder is annoying when cops look at you already...

If it comes down to it, i'll live with the 2 way, but if i can find a simple fix (s15, or r34 centre into my housing) for cheap, then i'll go with that

Edited November 21, 2005 by Bl4cK32

[SteveL]

Nissan must have thought they were better as they swapped using the vlsd for the hlsd from the s15, and the r34's...

<{POST_SNAPBACK}>

S15 centre is a Torsen, not a Quaife. It's actually what is known as a Torsen Type 2, which is not particularly strong due to the long, spindly nature of some of the internal connecting gears. The Torsen Type 1 is a much better design and used in some Toyota's, I believe. Don't know about R34's - I've only seen pictures - but the centre looks very similar to the S15 type.

[Bl4cK32]

i didnt say it was a Quaife...i said a hlsd

[Cubes]

The S15 runs the eact same diff center as the R34 GTR.

S15 diff being weak; what power level with what tyres are we looking at SteveL?

[mist]

Darren...

how could you want to sell the Nismo GT Pro?

Especially since you bought it from me freshly run in! haha.. It's such an awesome diff, you'll miss it when it's gone......

One my GT Pro in my S15, I found that setting the initial torque to medium made it nicer to drive. Sure it still clunks, but with regular oil changes (castrol diff oil, 75w140 i think) and the medium setting, it's a lot more tolerable. At lower speeds, just need to either work the clutch, or slide the tyres around

take care!

KJ

[SteveL]

The S15 runs the eact same diff center as the R34 GTR.

S15 diff being weak; what power level with what tyres are we looking at SteveL?

<{POST_SNAPBACK}>

It's actually torque that kills these - the achilles heal of the Quaife/Torsen centres is pretty much the same: sudden application of load to one wheel causes overload of the internal gears dues to the nature of the way they work. For example, lifting one wheel through a corner and then having the same wheel suddenly take up load again.